Caliper



Jan. 27, 1931.

c. v. MccARLEY GALIPER* Filed June 26, 1929 ao x www 7 @wr/ afg/226m@Gummi;

of the tool.

Patented dan.- 27, 1931 l applicati@ mea'r Jamas,

A My invention has for its object toprovide an eflicient measuring too'lwherein distances between two points are measured or vdetermined. rl`heinvention particularly relates to such tools' as Compasses and calipersand'it particularly provides a'simple me'ansfor ad-V justing tlie-pointsof such tools. t also pro- Y vides a construction wherein the legs maybeV readily replaced to change the character of the tool, as fromaccompass to an inside or outside caliper, or to a hermophroditecaliper. Y The-invention may be contained in tools of different formsandnsable for different purposes and, to illustrate a practicalapplication r of the invention, I have selected a structure containingthe invention as an example ofthe various embodiments of my inventiomandshall describe it hereinafter. The structure selected is shown in theaccompanyingdraw-v ings. A Fig. lisa perspectiveY View of the measureing tool selected as an example of the various constructions thatcontain my invention. Fig. 2 is a longitudinal section of the. head Fig.3 is a transversesec-tion taken on the plane of the line 3-3 indicatedin Fig. 2. Fig. llillustrates a tool that-mayV be used for openingthespring to provide for replacementofthe legs. Figs. 5, 6, and T,illustrate the various forms of legsthat may bel inserted in theinstrument, shown in Fig. l, for converting the compass into a caliperfor inside or outside measurement, or for hermophroditing.

The tool is provided kwith a pair of removable legs l having determiningpoints, such as the points 2. The legs are pivotally connected to a head3.l The head 321s provided with a slot 4 in which the ends of the legsmove. rThe Width of the slot l is, preferably, substantially the same asthe thickness of the metal of the ends of the legs whereby the headprevents any laterall play of the legs. 3 'A pin 5 extends through the'head 3 and transversely relative to the slot Ll. The leg-s l areprovided with notchesA 6 that fit the opposite sides of the pin 5. Aspringv band 7 surrounds the head 3 and engages the legs 50 1 at pointslocated intermediate the center .sfr-aras ear Y Y y cLAnKv. Mcoaarnir,oF TOLEDO, onto action'of the-lingers induced by the opera,-

Camlann 1929. 'sensi No. 373,699. ofthe pin 5 and. the endsof thelegsthat extend into the slot 4. 1 The ends'of the legs are, preferably,madev in the form of fingersl 8 that are inclined to the longitudinalaxes of the legs and thef55..VV

notchesv. have a total arcuatek lengthlthatis less than 360 degreeswhichpermitsv the engr-.lar movement of the legs labout the axis .of the pin5. Thespring band 7 elastically tends to `move the fingers so that their60 longitudi'nalv axes approach parallelism and thus tends to open orseparate thelegs l. The legs may thusjbe.adjustedrelative to each otherby limiting the movement induced by the operation of the spring-on thevlegs l. 65", To adjustablyj locatethe legs and, consequentlythe pointsv2 ofthe legs `relative to each other, a suitable member is adjustablypositioned in the head- 3 and located intermediate vthe lingers 8. Inthe form of construc-y 7o tionshown, a threaded pin l0 extends throughVa neck or a sleeve part 11 ofthe head 3 whichu is threaded to receivethe threaded pin. The end l2 of the pin 10 is cylindrical and lits abored part 13 ofthe head. The pinv l() may 47:5 ,c l

he rotated to adjust the lower endV ofthe cylindrical part ofthe pin tovary the angle between the ngers 8 and, consequently, to vary the anglebetween the legsrl. rlhe bore of the head 3 has a diameter that islarger so, than the slot a and consequently the head securely'maiiitainsthe cylindrical part 'l2 of `the pin 10 in alignment notwithstanding thepressure of the fingers 8 which is produced by theoperationof the spring7. A

In order to reduce friction and'to maintain a single point engagementalong the fingers 8 to secure uniform movement. of the legs l, in eachunit of length, of. movement of the pin l0, the'inner edges l5 of thelingers 8 may be sligthly curved and a ball 16' may be located in thebore 13 so as to engage the edges 15v of the lingers 8. The balll has adiameter substantially the vsame as that'of thel bore 13 and,consequently, itsv center will be maintained in the axis of the 'pin l0.v TWhen the ball 16 is forced from between the edges l5 of Ytheiingers 8by the wedging tion of the spring the ball will be located Ola-mf lesiev

Athe edges 15 iof the lingers with each other, the edges 17 are inclinedrelative to each other which enables lthe ball to spread the fingers toopenv them. If d esired, the edges 15 and 17 may be united to form acontinuous curved edge. Y

The pin is,`preferably,' provided with a skirt Q0 that surrounds thethreaded sleevev V11 of the head and an indicating scale may bevvlocated on the exterior suifaceof the sleeve' Y 11 to indicate therelative location or separa-V,

-merely spreading the spring.

` general character,

Ytion of the points 2 of the legs 1. rlhe pin is provided with twoknurled partsof dierent diameters, such as the'parts 25 and 26,whcrebyth'e pin may be slowly. or rapidly rotated to obtain the'adjustment desired by rolling the pin 10 between the fingers ofthe userof the instrument. A rapid movement of the part 2G will be causedjbyrolling the part between the iingers,'while the more slow movement willbe produced by .rolling the art 25 betweenthe ingers. The adjustmentofthe points 2 can be more accurately made byoperatingon the part 25 ofthe pin 10.v Preferably, the skirt 2O of the pin 10 is slotted as at 2T,and a clamping ring 28 is Alocated on the outside of the skirt 2O toclamp the skirt 20 against the surface of the sleeve part 11 ofthe head.The ring 28 is a split ring and may be provided with tlievscrew29 vforclamping the skirt 20 and, consequently, securing the pin 10 in anyposition to which it maybe adjustably moved by the operation of the pin10.V Preferably, the ysleeve part 11V extends through anv opening formedin the spring which operates to maintain the spring in position relativeto the other parts. lnasmuch as the legs 1 are connected only by thenotches that engage the pin 5, and by the parts of the edges of the legsthat are engaged by the ends of the springs, ythe legs 1 are readilyremovable from the instrument. They may be easily removed and insertedin position by Thus, the tool may be readily converted to any form ofmeasuring or determining tool of the same i i that is, it may be usedfor calipers or as a compass and-provides a convenient tool having partsso constructed that they may be readily replaced to form tools to beused for a variety of purposes. In constructions heretofore used, thelegs of such tools have interconnected parts that are usually riveted toand without mutilation the legs cannot be removed from the tool and.rconsequently, a mechanic requires as many complete tools as there arepurposes for which he wishes to use such tools. In the form ofconstruction shown, and because of the replaceability of its legs, acompass point 1 may be used in conjunction with an outside caliper leg30 or a compass leg lmay beused If desired, a combination of an outsidecali- For convenience ofspreading vthe ends of Y the spring band v7 toenable replacement of the legs, any suitable means may be used. lnFig. lis shown the spreader made in the form of lnippers having prongs 35 thatmay be inserted within the spring 7 and spread byY squeezing Vtogetherthe parts 36 that form the handleof the tool.v""1`his will spread the nends of the spring and permit removalv and replacement f I claim l Yv 1. In a measuring tool, ahead member having a slot and aneck, the'saidhead having an opening extending through the neck and tothe slot, a pinextending through the head and across the slot, a pair of legs hav-V ingnotches for engaging the pin on opposite sides thereof, a bow spring forengaging the legs to press the legs against fthe said pin andcooperating with the said pin for pivotally and elastically connectingthe legs to thev head, the legs having' protruding parts-located withinthe slot of the head, and 'means located within the neck for adjustingthe an gular position of the legs relative to each other. A I

2. 1n a measuring. tool, ahead member having a slot and a neck, thesaidhead having an opening extending through the neck and to the slot, apin rextending through the head and acrossv the slot, a pair of legshaving notches for engaging the pin on opposite sides thereof, a bowspring for engaging the legs to press the legs against the said pin andcooperating with the said pin for pivotally and elastically connectingthe legs to the legs having` protruding parts located within therslot ofthe head, the spring having an opening and the neck of the headprotruding through the opening ofthe spring, a ball carrying memberlocated in the neck, a ball located on the ball carrying member andadapted to Vengage between the protruding aarts of the legs located inthe slots, whereby movement of the member in the` neck will vary thevlocation of the points of the legs relative to each other.

In witness whereof have hereunto signed my name to this specification.

, n CLARK V. MCCARLEY.

in conjunction with an inside caliper leg 31. i

head, the

